1. Field of the Invention
This invention relates to a disposable diaper for the use of infants, adults or incontinent persons.
2. Description of the Prior Art
Heretofore, many kinds of disposable diapers have been proposed. One typical disposable diaper is a so-called flat type which comprises a liquid permeable top sheet, a liquid impermeable back sheet, an absorbent member disposed therebetween, and a pair of side flaps, a pair of tape fasteners, disposed at both side edges of a waist portion on the back side of the side flaps, being fastened to the wearer's stomach side. Another example of such flat type disposable diaper is a disposable diaper 1 shown in FIG. 11. As is shown in FIG. 11, the disposable diaper 1 comprises, like the above-mentioned flat type disposable diaper, a top sheet 2, a back sheet 3, an absorbent member 4, and a pair of side flaps 15, 15, waist portions 15A, 15A in the back side of the side flaps 15, 15 being expanded sidewardly respectively, thereby forming a pair of expanded portions for covering the wearer's body portion, a pair of tape fasteners 16, 16 each provided to the corresponding expanded portions being fastened to an area-to-be-fastened 18 formed on a waist body portion 7 in the stomach side. Leg portions 15B and waist body portions 17 in the side flaps 15, 15 are provided with elastic members 19 and 110, respectively, in order to enhance fitness when the wearer wears the disposable diaper (Japanese Patent Publication No. Sho 52-40267).
Recently, a so-called underpants or drawers type disposable diaper was proposed, in which both side edges in the stomach side and back side of a pair of side flaps are attached and fixed together to form a pair of leg opening portions and a pair of waist opening portions, respectively (Japanese Patent Early Laid-open Publication No. Sho 61-207606). This drawers type disposable diaper is expansible at the leg and waist opening portions respectively so that it is intimately fitted to the wearer regardless of the wearer's figure. The wearer can usually wear such drawers type disposable diaper in the wearer's standing attitude. Therefore, this is very useful when used as toilet training, or for the-use of incontinent persons or adults who have difficulty in walking. Such drawers type disposable diaper also has an appearance of sewing finish which a good sewn product usually has and is intentionally made as a disposable underwear.
However, although the conventional drawers type disposable diaper has a flexible fitness to infants of high months age who moves actively, it has as a shortcoming that since the size of the waist opening portion is limited, it is difficult for the wearer to insert legs smoothly and the wear usually gives a feel of being narrow and tight. When the wearer flutters the feet, even more difficulty is encountered for wearing such drawers type disposable diaper. Moreover, the conventional drawers type disposable diaper has also a shortcoming that the wearer is always compel led to keep an awkward attitude when wearing whether the disposable diaper is for the use of infants or adults.
Furthermore, the conventional drawers type disposable diaper has as a shortcoming that it is not easy to tell whether there are waste materials discharged in the diaper while the wearer wears the diaper, which requires relying on the wearer's expression as an indication in order to make sure that the waste materials are already therein. Moreover, since no tape fastener is provided, it has another shortcoming that when the used disposable diaper is disposed, it is impossible to fasten the diaper using a tape fastener after waste materials are wrapped up within the diaper.